Event narrative (NOAA)
Up to 9 inches of rain fell in a 6 to 10 hour period causing widespread flash flooding. The heaviest rain axis extended from East St. Louis southeastward towards Mascoutah. Numerous roads were flooded, including northbound I-55 at I-64, ramps from I-64 to I-255, U.S. Highway 50 between O'Fallon and Lebanon, and Illinois Route 15 near intersection with Frank Scott Parkway. Several water rescues were performed including on Illinois Route 15 at Karch Road, east of Freeburg and on West F Street near North 3rd Street in Belleville. An estimated 600 St. Clair County households were damaged by flash flooding. The St. Clair County Animal Shelter was flooded in Belleville so several dozen dogs and some cats had to be evacuated and placed in other shelters or homes temporarily. Overall, no injuries
Other notable flash flood events in Illinois
Source: NOAA/NCEI Storm Events Database. Deaths and injuries are those NOAA classifies as direct. Damage is the reporting office's estimate at the time and is not inflation-adjusted. This is a catalogue record, not a forecast.